Cardiac treatment devices and methods

ABSTRACT

Devices and methods provide for ablation of cardiac tissue for treating cardiac arrhythmias such as atrial fibrillation. Although the devices and methods are often be used to ablate epicardial tissue in the vicinity of at least one pulmonary vein, various embodiments may be used to ablate other cardiac tissues in other locations on a heart. Devices generally include at least one tissue contacting member for contacting epicardial tissue and securing the ablation device to the epicardial tissue, and at least one ablation member for ablating the tissue. Various embodiments include features, such as suction apertures, which enable the device to attach to the epicardial surface with sufficient strength to allow the tissue to be stabilized via the device. For example, some embodiments may be used to stabilize a beating heart to enable a beating heart ablation procedure. Many of the devices may be introduced into a patient via minimally invasive introducer devices and the like. Although devices and methods of the invention may be used to ablate epicardial tissue to treat atrial fibrillation, they may also be used in veterinary or research contexts, to treat various heart conditions other than atrial fibrillation and/or to ablate cardiac tissue other than the epicardium.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] The present application is a continuation-in-part applicationwhich claims priority to U.S. patent application Ser. No. 10/272,446,which was filed Oct. 15, 2002, which claims priority to U.S. ProvisionalPatent Application Serial No. 60/337,070, filed Dec. 4, 2001, entitled“Methods and Devices for the Least Invasive Cardiac Surgery of AtrialFibrillation,” and the entire contents of these applications are herebyincorporated by reference.

BACKGROUND OF THE INVENTION

[0002] The present invention relates generally to medical devices andmethods. More specifically, the invention relates to devices and methodsfor ablating epicardial tissue to treat cardiac arrhythmias such asatrial fibrillation.

[0003] Atrial fibrillation (AF) is a heart beat rhythm disorder (or“cardiac arrhythmia”) in which the upper chambers of the heart known asthe atria quiver rapidly instead of beating in a steady rhythm. Thisrapid quivering reduces the heart's ability to properly function as apump. AF is characterized by circular waves of electrical impulses thattravel across the atria in a continuous cycle. It is the most commonclinical heart arrhythmia, affecting more than two million people in theUnited States and some six million people worldwide.

[0004] Atrial fibrillation typically increases the risk of acquiring anumber of potentially deadly complications, including thrombo-embolicstroke, dilated cardiomyopathy and congestive heart failure. Quality oflife is also impaired by common AF symptoms such as palpitations, chestpain, dyspnea, fatigue and dizziness. People with AF have, on average, afive-fold increase in morbidity and a two-fold increase in mortalitycompared to people with normal sinus rhythm. One of every six strokes inthe U.S. (some 120,000 per year) occurs in patients with AF, and thecondition is responsible for one-third of all hospitalizations relatedto cardiac rhythm disturbances (over 360,000 per year), resulting inbillions of dollars in annual healthcare expenditures.

[0005] AF is the most common arrhythmia seen by physicians, and theprevalence of AF is growing rapidly as the population ages. Thelikelihood of developing AF increases dramatically as people age; thedisorder is found in about 1% of the adult population as a whole, and inabout 6% of those over age 60. By age 80, about 9% of people (one in 11)will have AF. According to a recent statistical analysis, the prevalenceof AF in the U.S. will more than double by the year 2050, as theproportion of elderly increases. A recent study called TheAnticoagulation and Risk Factors in Atrial Fibrillation (ATRIA) study,published in the Spring of 2001 in the Journal of the American MedicalAssociation (JAMA), found that 2.3 million U.S. adults currently have AFand this number is likely to increase over the next 50 years to morethan 5.6 million, more than half of whom will be age 80 or over.

[0006] As the prevalence of AF increases, so will the number of peoplewho develop debilitating or life-threatening complications, such asstroke. According to Framingham Heart Study data, the stroke rate in AFpatients increases from about 3% of those aged 50-59 to more than 7% ofthose aged 80 and over. AF is responsible up to 35% of the strokes thatoccur in people older than age 85.

[0007] Efforts to prevent stroke in AF patients have so far focusedprimarily on the use of anticoagulant and antiplatelet drugs, such aswarfarin and aspirin. Long-term warfarin therapy is recommended for allAF patients with one or more stroke risk factors, including all patientsover age 75. Studies have shown, however, that warfarin tends to beunder-prescribed for AF. Despite the fact that warfarin reduces strokerisk by 60% or more, only 40% of patients age 65-74 and 20% of patientsover age 80 take the medication, and probably fewer than half are on thecorrect dosage. Patient compliance with warfarin is problematic, and thedrug requires vigilant blood monitoring to reduce the risk of bleedingcomplications.

[0008] Electrophysiologists classify AF by the “three Ps”: paroxysmal,persistent, or permanent. Paroxysmal AF—characterized by sporadic,usually self-limiting episodes lasting less than 48 hours—is the mostamenable to treatment, while persistent or permanent AF is much moreresistant to known therapies. Researchers now know that AF is aself-perpetuating disease and that abnormal atrial rhythms tend toinitiate or trigger more abnormal rhythms. Thus, the more episodes apatient experiences and the longer the episodes last, the less chance ofconverting the heart to a persistent normal rhythm, regardless of thetreatment method.

[0009] AF is characterized by circular waves of electrical impulses thattravel across the atria in a continuous cycle, causing the upperchambers of the heart to quiver rapidly. At least six differentlocations in the atria have been identified where these waves cancirculate, a finding that paved the way for maze-type ablationtherapies. More recently, researchers have identified the pulmonaryveins as perhaps the most common area where AF-triggering foci reside.Technologies designed to isolate the pulmonary veins or ablate specificpulmonary foci appear to be very promising and are the focus of much ofthe current research in catheter-based ablation techniques.

[0010] Although cardiac ablation devices and methods are currentlyavailable, many advances may still be made to provide improved devicesand methods for ablating-epicardial tissue to treat AF and otherarrhythmias. For example, currently available devices can be difficultto position and secure on epicardial tissue to perform an ablation.Devices such as bipolar ablation clamps and others can ablate tissueonly in very limited patterns, such as one or two straight lines.Ablation devices often have no means for shielding ablative energy, toavoid unwanted burning of tissues in the vicinity of the heart, such asthe esophagus. Relatively few devices can be secured to epicardialtissue with sufficient force to allow for stabilization of the heart.And many ablation devices may not be introduced by minimally invasivemeans, thus requiring an open surgical procedure. Typically, therefore,current cardiac ablation procedures for AF treatment still requirestopping the heart and using a cardiopulmonary bypass apparatus.

[0011] Therefore, a need exists for improved devices and methods forablating epicardial tissue to treat AF and other cardiac arrhythmias.Preferably, such devices and methods would provide ablation adjacent toand/or encircling one or more pulmonary veins, to disrupt conductionpathways and thus partially or completely treat AF. Also preferably,such devices and methods would allow for minimally invasive ablationprocedures, in some cases on a beating heart. Such devices might alsoprovide additional advantages, such as advantageous ablation patterns,shielding of ablative energy and/or the like. At least some of theseobjectives will be met by the present invention.

BRIEF SUMMARY OF THE INVENTION

[0012] Devices and methods of the present invention provide for ablationof cardiac tissue for treating cardiac arrhythmias such as atrialfibrillation. Although the devices and methods are often used to ablateepicardial tissue in the vicinity of at least one pulmonary vein,various embodiments may be used to ablate other cardiac tissues in otherlocations on a heart. Generally, devices of the invention include atissue contacting member for contacting a portion of the epicardialtissue of a heart and securing the ablation device to the epicardialtissue, and an ablation member for ablating at least a portion of thetissue. In various embodiments, the devices have features which enablethe device to attach to the epicardial surface with sufficient strengthto allow the tissue to be stabilized via the device. For example, someembodiments may be used to stabilize a beating heart to enable a beatingheart ablation procedure. Many of the devices may be introduced into apatient via minimally invasive incisions, introducer devices and thelike. Although much of the following description focuses on usingdevices and methods of the invention to treat atrial fibrillation (AF)by ablating epicardial tissue on a human heart, the devices and methodsmay be used in veterinary or research contexts, to treat various heartconditions other than atrial fibrillation and/or to ablate cardiactissue other than the epicardium.

[0013] In one aspect, a system for treating heart tissue to treat acardiac arrhythmia comprises: at least one energy transmission memberfor applying energy to the heart tissue in a pattern to treat thecardiac arrhythmia; at least one tissue securing member coupled with theat least one energy transmission member for enhancing contact of theenergy transmission member with the heart tissue; and at least oneguiding member coupled with at least one of the energy transmissionmember and the tissue securing member for guiding the energytransmission member and the tissue securing member to a location fortreating the heart tissue.

[0014] Optionally, such as system may further include at least onevisualization member for enhancing visualization of the heart tissue andthe treatment location. In some embodiments, for example, thevisualization member may include an optic imaging device, a thermalimaging device, an ultrasound device, an electrical imaging device, aDoppler imaging device or the like, though any suitable device may beused. In some embodiments, an optic imaging device comprises a fiberoptic device positionable to view a posterior portion of the hearttissue. In other embodiments, a thermal imaging device measures at leastone heat transfer coefficient of the heart tissue to determine at leastone of a type and a thickness of the heart tissue. In still otherembodiments, an electrical imaging device measures electrical resistanceand/or impedance of the heart tissue to determine a type and/or athickness of the heart tissue.

[0015] In some embodiments, the at least one visualization member isremovably coupled with at least one of the at least one energytransmission member, the at least one tissue securing member and the atleast one guiding member. Also in some embodiments, the at least onevisualization member may comprise at least one optic member foracquiring optic signals of an area to be visualized, and wherein thevisualization member includes at least one inflatable member coupledwith the visualization member at or near the optic member. For example,the inflatable member may provide a space in a body cavity and/orbetween at least two body tissues to enhance operation of the opticmember. In some embodiments, the inflatable member includes an inflationport in fluid communication with an inflation lumen coupled with thevisualization member for allowing introduction of a liquid or a gas toinflate the inflatable member. In some embodiments, the inflatablemember reduces motion of the heart tissue when applied to the hearttissue.

[0016] Some embodiments of the invention also include at least onepositioning device for contacting the heart tissue and positioning theheart tissue for treatment. For example, the positioning device maycomprise a suction positioning device. In some embodiments, thepositioning device reduces motion of a beating heart to further positionthe heart tissue for treatment.

[0017] The energy applied to the heart tissue may be any suitableenergy, such as but not limited to radio frequency energy, ultrasoundenergy, microwave energy, cryogenic energy, thermoelectric energy andlaser energy. In some embodiments, optionally, the energy transmissionmember contacts an epicardial surface of the heart tissue to transmitthe energy, and wherein the energy is transmitted from the epicardialsurface through the heart tissue to an endocardial surface. Sometimes,the energy is further transmitted through at least one of fat andconnective tissue covering at least part of the epicardial surface. Someembodiments also include at least one grounding device for dispersingthe energy from a patient undergoing an energy transmission heartprocedure. Some embodiments may also include at least one needle coupledwith the energy transmission member for insertion into the heart tissueto enhance the application of energy to the heart tissue. In some ofthese embodiments, the energy is transmitted from a tip of each needle.Optionally, the needle may be retractable. In some embodiments, forexample, the retractable needle is exposed and retracted via a pneumaticmember coupled with the energy transmission member. In some embodiments,the retractable needle is exposed and retracted automatically when theenergy transmission member contacts the heart tissue. Also in someembodiments, the depth of penetration of the retractable needle into theheart tissue is adjustable.

[0018] Some embodiments may also include at least one closed circuitfeedback loop for measuring and regulating operation of the energytransmission member. In some embodiments, either the energy transmissionmember or the tissue securing member further comprises at least onefluid aperture for applying fluid to the heart tissue to enhance theapplication of energy to the heart tissue.

[0019] In some embodiments, the energy transmission member is coupledwith at least one guiding member such that a change in shape of theguiding member causes a corresponding change in shape of the energytransmission member. For example, the guiding member may comprise adeformable linear member its shape being adjustable by a user, andwherein the energy transmission member comprises a deformable linearmember coaxially coupled with the guiding member so as to move with theguiding member. In some embodiments, the guiding member is adjustable toat least partially encircle at least one pulmonary vein.

[0020] In some embodiments, the tissue securing member includes at leastone connector for removably coupling with the at least one energytransmission member. Sometimes, the tissue securing member isconformable to a surface topography of the heart tissue. In variousembodiments, a first longitudinal axis of the tissue securing member anda second longitudinal axis of the removably coupled energy transmissionmember may be collinear, parallel to one another or offset from oneanother. In some embodiments, the energy transmission member comprises alinear member, and the connector comprises a plurality of connectorsdisposed along a length of the tissue securing member for removablycoupling the linear member with the tissue securing member. The tissuesecuring member may allow compressive force to be applied between the atleast one energy transmission member and the heart tissue.

[0021] In some embodiments, the tissue securing member comprises atleast one vacuum applying member. The vacuum applying member maycomprise, for example: at least one vacuum lumen; at least one vacuumport in fluid communication with the lumen for coupling the lumen with avacuum source; and at least one aperture in fluid communication with thelumen for applying vacuum force to the heart tissue. In someembodiments, the vacuum lumen comprises multiple, separate lumens, andeach separate lumen is in fluid communication with a separate vacuumport. Such embodiments may optionally further include means forselectively applying vacuum to one or more of the separate lumenswithout applying vacuum to one or more other separate lumens.

[0022] In other embodiments, the tissue securing member comprises atleast one expansible balloon member. The expansible balloon member mayinclude at least one fluid introduction port for allowing introductionof a liquid or a gas to expand the balloon member. Some embodimentsinclude multiple, separate balloon members, wherein each separateballoon member is in fluid communication with a separate fluidintroduction port. Such embodiments may also include means forselectively introducing fluid into one or more of the separate balloonswithout introducing fluid into one or more other separate balloons.Optionally, in some embodiments, the tissue securing member prevents aportion of the heart tissue from being treated by the at least oneenergy transmission member. For example, the tissue securing member maycomprise at least one insulation material for preventing the portion ofthe heart tissue from being treated. In one embodiment, the insulationmaterial further prevents the at least one energy transmission memberfrom contacting or harming other, non-cardiac tissue of the patient andfrom contacting or harming a user of the energy transmission member.

[0023] In some embodiments, the guiding member comprises at least one ofan elongate shaft, a steerable guidewire and an introducer sheath. Forexample, the steerable guidewire may comprise a pushable guidewirehaving at least one relatively stiff portion and one relatively flexibleportion for positioning the energy transmission member in a location fortreatment. For example, the steerable guidewire may comprise a pullableguidewire to which tension is applied to steer the guidewire to positionthe energy transmission member in a location for treatment.

[0024] In another aspect, a system for treating heart tissue to treat acardiac arrhythmia comprises: at least one therapeutic agenttransmission member for applying at least one therapeutic agent to theheart tissue in a pattern to treat the cardiac arrhythmia; at least onetissue securing member coupled with the at least one energy transmissionmember for enhancing contact of the energy transmission member with theheart tissue; and at least one guiding member coupled with at least oneof the energy transmission member and the tissue securing member forguiding the energy transmission member and the tissue securing member toa location for treating the heart tissue. In some embodiments, forexample, the therapeutic agent transmission member comprises at leastone lumen and at least one aperture in the lumen for allowing passage ofthe at least one therapeutic agent out of the lumen to contact the hearttissue.

[0025] Optionally, such a system may further include at least one needlecoupled with the therapeutic agent transmission member for insertioninto the heart tissue to enhance application of the at least onetherapeutic agent to the heart tissue. The therapeutic agenttransmission member itself may comprise at least one needle and at leastone aperture adjacent a tip of each needle for allowing passage of theat least one therapeutic agent out of the needle to contact the hearttissue. Optionally, the needle may be retractable. For example, theretractable needle may be exposed and retracted via a pneumatic membercoupled with the therapeutic agent transmission member. In someembodiments, the retractable needle is exposed and retractedautomatically when the therapeutic agent transmission member contactsthe heart tissue. Also in some embodiments, a depth of penetration ofthe retractable needle into the heart tissue is adjustable.

[0026] In another aspect of the invention, a method for treating hearttissue of a patient to treat a cardiac arrhythmia involves: advancing atleast one treatment member coupled with at least one tissue securingmember through an incision on the patient; visualizing a treatment areain the patient with at least one visualization member; contacting theheart tissue of the patient with the treatment member and the tissuesecuring member; applying a force, through the tissue securing member,to enhance contact of the treatment member with the heart tissue; andtreating the heart tissue, using the at least one treatment member. Insome embodiments, the treatment member and/or the tissue securing memberare advanced through a port applied to the patient, the port having adiameter no greater than 5 cm.

[0027] In some embodiments, the advancing step includes guiding thetreatment member and/or the tissue securing member using at least oneguiding member. Guiding may involve, for example, using a pushableguidewire having at least one relatively stiff portion and onerelatively flexible portion for positioning the treatment member in alocation for treatment. Alternatively, guiding may involve using apullable guidewire to which tension is applied to steer the guidewire toposition the treatment member in a location for treatment.

[0028] Some embodiments of the method further include using at least onepositioning device to position the heart tissue for treatment. This mayinvolve, for example, applying suction to the heart tissue. In someembodiments, using the positioning device reduces motion of the hearttissue. In other embodiments, contacting the heart tissue comprisesapplying a suction force with the tissue securing member to increase acontact surface area of the tissue securing member with the hearttissue. Applying the suction force may further comprise providingconsistent contact force between the heart tissue and the tissuesecuring member. Optinoally, applying the suction force may comprisesecuring the tissue securing member and the treatment member to theheart tissue, the tissue securing member and the treatment member havingthe same cross-sectional shape.

[0029] In some embodiments, treating the heart tissue comprises applyingenergy to the heart tissue in a pattern to reduce or eliminate thecardiac arrhythmia. The applied energy may be in any suitable form, suchas radio frequency energy, ultrasound energy, microwave energy,cryogenic energy, thermoelectric energy or laser energy. In someembodiments, the energy is applied to an epicardial surface of theheart, wherein the energy is transmitted from the epicardial surfacethrough the heart tissue to an endocardial surface. Optionally, theenergy may be further transmitted through fat and/or connective tissuecovering at least part of the epicardial surface. Some methods mayfurther include dispersing the energy from the patient through at leastone grounding device coupled with the patient.

[0030] Some embodiments further involve inserting at least one needleinto the heart tissue to enhance the application of energy to the hearttissue. For example, the energy may transmitted from a tip of eachneedle. Some methods include extending the at least one needle from aretracted position before applying the energy and retracting the atleast one needle to the retracted position when the energy has beenapplied. Such methods may also include selecting a depth of penetrationof the at least one retractable needle into the heart tissue. Otherembodiments may involve measuring the application of energy to the hearttissue using at least one closed circuit feedback loop and regulatingthe application of energy to the heart tissue based on the measurement.Still other embodiments may include applying fluid to the heart tissueto enhance the application of energy to the heart tissue.

[0031] In alternative embodiments, treating the heart tissue comprisesapplying at least one therapeutic agent to the heart tissue in a patternto reduce or eliminate the cardiac arrhythmia. For example, applying theat least one therapeutic agent may involve infusing the agent through atleast one aperture in the at least one treatment member. In someembodiments, the therapeutic agent is infused through at least oneaperture in at least one needle coupled with the treatment member. Insome embodiments, applying the at least one therapeutic agent comprisesinserting at least one needle into the heart tissue to a desired depth,injecting the at least one agent into the heart tissue, and removing theat least one needle from the heart tissue. Such a method may furtherinclude extending the at least one needle from a retracted position forinsertion into the heart tissue and retracting the at least one needleto the retracted position after injection.

[0032] Yet another embodiment may include adjusting a shape of a guidingmember coupled with the at least one treatment member to alter the shapeof the treatment member. In some embodiments, adjusting the shape of theguiding member allows the treatment member to conform to a surface ofthe heart tissue. Also in some embodiments, adjusting the shape of theguiding member allows the treatment member to at least partiallyencircle at least one pulmonary vein. Some embodiments may also includeremovably coupling the tissue securing member with the at least onetreatment member. Some embodiments may further include conforming thetissue securing member to a surface topography of the heart tissue.

[0033] In some embodiments, applying force comprises applyingcompressive force between the at least one treatment member and theheart tissue. Applying the compressive force, in turn, may comprisesapplying vacuum force via at least one vacuum member of the tissuesecuring member. Such methods may further involve applying the vacuumforce through at least a portion of the vacuum member while not applyingthe vacuum force through at least another portion of the vacuum member.In some embodiments, applying the compressive force comprises applyingforce via at least one expansible balloon member. A method may furthercomprising preventing, using the tissue securing member, a portion ofthe heart tissue from being treated by the at least one treatmentmember. For example, the tissue securing member may comprise at leastone insulation material for preventing the portion of the heart tissuefrom being treated.

[0034] In some embodiments, visualizing comprises using at least onevisualization member selected from the group consisting of an opticimaging device, a thermal imaging device, an ultrasound device, anelectrical imaging device and a Doppler imaging device. Some embodimentsalso include expanding an expansible balloon coupled with thevisualization member near an optic element to enhance visualization.Sometimes, expanding the balloon provides a space in a body cavityand/or between at least two body tissues to enhance operation of theoptic member. Optionally, expanding the balloon may reduce motion of theheart tissue when applied to the heart tissue.

[0035] In yet another aspect, a method for treating heart tissue of apatient to treat a cardiac arrhythmia comprises: advancing at least onetreatment member and at least one tissue securing member through anincision on the patient; removably coupling the at least one treatmentmember with the at least one tissue securing member; visualizing atreatment area in the patient with at least one visualization member;contacting the heart tissue of the patient with the treatment member andthe tissue securing member; applying a force, through the tissuesecuring member, to enhance contact of the treatment member with theheart tissue; and treating the heart tissue, using the at least onetreatment member. In some embodiments, and treatment member is advancedthrough the tissue securing member. Optionally, in some embodiments, thetreatment member and the tissue securing member are advanced through aminimally invasive port applied to the patient.

[0036] Various embodiments of the devices and methods described brieflyabove are further described in the appended drawings and the followingdetailed description. The description of specific embodiments isprovided for exemplary purposes and should not be interpreted to narrowthe scope of the invention as defined in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0037]FIG. 1 is a perspective view illustration of a human heart and anablation device in position for performing an ablation procedure,according to one embodiment of the invention.

[0038]FIG. 2 is a perspective view of an ablation device, according toone embodiment of the invention.

[0039]FIG. 2a is a perspective view of the ablation device shown in FIG.2, with the ablation member removed.

[0040]FIG. 3 is a bottom-surface view of an ablation device, accordingto one embodiment of the invention.

[0041]FIG. 4 is a perspective view of a flexible, elongate ablationdevice with two rows of suction apertures, according to one embodimentof the invention.

[0042]FIG. 4a is a bottom-surface view of the ablation device as shownin FIG. 4, with the ablation member removed.

[0043]FIG. 5 is a bottom-side view of a flexible, elongate ablationdevice with one row of suction apertures, according to one embodiment ofthe invention.

[0044]FIG. 6 is a perspective view of a human heart and an ablationdevice in position for performing an ablation procedure, according toone embodiment of the invention.

[0045]FIG. 7 is a perspective view of an elongate shaft ablation device,according to one embodiment of the invention.

[0046]FIG. 7a is a perspective view of the distal end of a shaft as inFIG. 6, with straight jaws, according to one embodiment of theinvention.

[0047]FIG. 8 is a perspective view of a human heart and an elongateshaft ablation device in position for ablating cardiac tissue, accordingto one embodiment of the invention.

[0048]FIG. 9 is a block diagram of a method for ablating tissueaccording to one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0049] The present invention relates generally to medical devices andmethods and more specifically to devices and methods for ablatingcardiac tissue for treating cardiac arrhythmias such as atrialfibrillation. Ablation of cardiac tissue in various patterns has beenshown to disrupt conduction pathways in the heart to ameliorate oreliminate AF or other arrhythmias. The devices and methods will often beused to ablate epicardial tissue in the vicinity of at least onepulmonary vein, but various embodiments may be used to ablate othercardiac tissues in other locations on a heart.

[0050] Generally, ablation devices of the invention include at least onetissue contacting member for contacting a portion of the epicardialtissue of a heart, securing means for securing the ablation device tothe tissue and at least one ablation member coupled with the contactingmember for ablating at least a portion of the tissue. In variousembodiments, the devices have features which enable the device to attachto the epicardial surface with sufficient strength to allow the tissueto be stabilized via the device. For example, some embodiments may usesuction force to secure the device to epicardial tissue and stabilize abeating heart to enable a beating heart ablation procedure. Otherembodiments may include other optional features, such as sensors forsensing whether tissue has been ablated, a support member with an armfor connecting the device to a positioning device, cooling apparatus forcooling epicardial tissue, visualization devices and/or the like. Someembodiments of the device are introducible into a patient via minimallyinvasive means, such as a minimally invasive incision, sheath, trocar orthe like.

[0051] Methods of the invention generally include contacting a devicewith epicardial tissue, using a tissue contacting member on the deviceto secure the device to the tissue, and ablating the tissue with anablation member on the device. In some embodiments, the method furtherincludes additional steps such as positioning the device on theepicardial tissue, stabilizing cardiac tissue, cooling cardiac tissue,positioning the device using a positioning device, visualizingepicardial tissue with an imaging device and/or the like. Again,although much of the following description focuses on embodiments usedto treat AF by ablating epicardial tissue near one or more pulmonaryveins on a human heart, the devices and methods may be used inveterinary or research contexts, to treat various heart conditions otherthan AF, to ablate cardiac tissue other than the epicardium and/or inany other suitable manner or context.

[0052] Referring now to FIG. 1, an ablation device 100 is shown inposition for ablating epicardial tissue on a human heart 140. A top viewof ablation device 100 is shown, the visible components of device 100including a tissue contacting member 102 coupled with a suctionconnector 216 and a support member 104 having a support arm 106. Tissuecontacting member 102 also includes multiple artery securing arms 108for securing one or more coronary arteries. Suction connector 216 iscoupled with a suction cannula 112, which in turn is coupled with asuction source 120. Support arm 106 is coupled via a clamp 116 to apositioner 114, which in turn is coupled to a stabilizing device 118 forstabilizing positioner 114. Finally, an ablation member (not visible) ofablation device 100 is coupled, via a wire 110, to an energy source 122.In various embodiments, ablation device 100 may be introduced into apatient through a minimally invasive introducer device, such as a sheath124, trocar or the like, as is represented in FIG. 1 by a simplifiedrepresentation of sheath 124.

[0053] In FIG. 1, ablation device 100 is shown in a position partiallyencircling the right superior pulmonary vein 142 and the right inferiorpulmonary vein 144. As will be described in further detail below, such aposition is only one possible configuration for treating heart 140. Inother embodiments, for example, both of the right pulmonary veins 142,144 may be completely encircled, only one may be partially or completelyencircled, the left superior 148 and/or left inferior 150 pulmonaryveins may be partially or completely encircled and/or various patternsmay be ablated on the left atrium 146, the right atrium 152 and/or theright and left ventricles (not labeled). Any ablation pattern suitablefor heart treatment may be accomplished by one or more embodiments ofthe present invention. Thus, the following descriptions of variousembodiments should not be interpreted to narrow the scope of theinvention as set forth in the claims.

[0054] Generally, ablation device 100 includes at least one tissuecontacting member 102 coupled with at least one ablation member (notshown in FIG. 1). One embodiment of a device which may be used as tissuecontacting member 102 is described in U.S. Patent Application Serial No.60/182,048, filed on Feb. 11, 2000, the entire contents of which ishereby incorporated by reference. Ablation device 100 shown in FIG. 1actually includes two tissue contacting members 102, one on either sideof the right pulmonary veins 142, 144. Tissue contacting members 102 maybe coupled together via support member 104 and suction connector 216. Inother embodiments, some of which will be described below, tissuecontacting member 102 may include only one member, more than twomembers, a coupling member disposed between multiple arms and/or thelike. Alternatively, tissue contacting member 102 may be conical,linear, shaped as a flat pad or a flat elongate member or may have anyother suitable configuration. Additionally, tissue contacting members102 may have any suitable size and dimensions. For example, in FIG. 1,tissue contacting members 102 and device 100 in general have a shape anddimensions to contact and ablate epicardial tissue on heart 140 in apattern partial encircling the right pulmonary veins 142, 144. Manyother configurations and sizes are possible, as described further below.

[0055] Tissue contacting members 102 may be manufactured from anysuitable material, such as a polymer, plastic, ceramic, a combination ofmaterials or the like. In one embodiment, for example, tissue contactingmembers 102 are manufactured from a liquid molded silicone rubber. Insome embodiments, the material used to make tissue contacting members102 is chosen to allow the members 102 to be at least partiallydeformable or malleable. Deformable tissue contacting members 102 mayallow ablation device 100 to be inserted into a patient and/or advancedto a surgical site within the patient via a minimally invasive incisionor a minimally invasive introducer device, such as sheath 124.Deformable tissue contacting members 102 may also allow device 100 toconform to a surface of heart 140, to enhance ablation of epicardial orother cardiac tissue. In some embodiments, tissue contacting members 102include one or more artery securing arms 108, for securing, exposingand/or occluding one or more coronary arteries via silastic tubingattached between the artery and securing arm 108. Securing arms 108 aregenerally made of the same material(s) as tissue contacting members 102but may also suitably comprise other materials.

[0056] In some embodiments, tissue contacting members 102 are coupledwith support member 104. Support member 104 may be made of any suitablebiocompatible material, such as titanium, stainless steel, nickeltitanium alloy (Nitinol) or the like. Support member 104 may be coupledwith tissue contacting members 102 by any suitable means, such as butnot limited to one or more adhesive substances, placement of a portionof support member 104 within a sleeve on tissue contacting members 102or a combination of both. Like tissue contacting members 102, supportmember 104 may also be malleable or deformable to allow for insertion ofablation device 100 through a minimally invasive sheath 124 and/or forenhancing conformability of device 100 to a surface of heart 140.Support member 104 typically includes at least one support arm 106 orsimilar protrusion or multiple protrusions for removably couplingablation device 100 with positioner 114 or one or more other positioningdevices. Positioner 114, for example, may comprise a flexible,positioning arm, with attachment means such as clamp 116 for attachingto support arm 106 and stabilizing device 118 for stabilizing positioner114. For example, a flexible, articulating positioner 114 may be of thetype which rigidities when tensile force is applied, such as via atensioning wire. Any other suitable positioner 114 may alternatively beused. In other embodiments, device 100 may not include support member104. Such devices 100 may incorporate a connection arm onto a tissuecontacting member 102, may be positioned on heart 140 using apositioning device inserted through a separate incision, or may bepositioned or manipulated by a physician or other user via any othersuitable means.

[0057] Tissue contacting members 102 may also be coupled with one ormore suction cannulas 112 to provide suction for enhancing contact ofablation device 100 with epicardial tissue. In various embodiments,tissue contacting members 102 may be directly coupled to one or morecannulas 112 or may be connected via one or more suction connectors 216.In FIG. 1, a V-shaped suction connector is used to couple the two tissuecontacting members 102 with a common cannula 112. Cannula 112, in turn,is connected to suction source 120, which may be a conventional wallsuction or stand-alone suction source. Generally, cannula 112 may be anysuitable conventional cannula 112, which are well known to those skilledin the art. Suction connector 216 is typically comprised of the samematerial(s) as tissue contacting members 102, but may also be made of amaterial or materials used to make cannula 112. Suction connector 216may further include a nozzle 218 (FIG. 2) for connecting to cannula 112.

[0058] Ablation device 100 also includes at least one ablation member210 (FIG. 2). Ablation member 210 typically receives energy from aseparate energy source 122, although ablation members 210 with internalenergy sources are also contemplated. Where a separate energy source 122is used, ablation member 210 may be coupled with source 122 by anysuitable means. In one embodiment, for example, ablation member 210 maybe coupled to energy source 122 with wire 110. Wire 110 may be anysuitable connector, such as fiber optic cable, electric cable, coaxialcable, ultrasound transmission device or the like. As is describedfurther below, any suitable energy may be provided by energy source 122for ablation and any means for transmitting energy to ablation member210 is contemplated within the scope of the invention. In someembodiments, for example, energy may be transmitted remotely, so that nowires or other similar connecting devices are required. In otherembodiments, radio frequency energy may be provided by an RF energysource and transmitted to ablation member 210 via conventionalelectrical wire(s) 110.

[0059] Generally, ablation member 210 may be configured to transmitenergy of any suitable quantity or force. For example, in someembodiments sufficient energy will be transmitted through ablationmember 210 to ablate only epicardial tissue on a heart. In otherembodiments, sufficient energy may be transmitted to cause one or morelayers beneath the epicardial tissue to be ablated. In some embodiments,for example, one or more transmural lesions (across the entire wall ofthe heart) may be ablated. Typically, an amount of energy transmittedthrough ablation member 210 will be adjustable to create an desiredablation depth.

[0060] As mentioned briefly above, a minimally invasive introducersheath 124, trocar or other minimally invasive device may be used forintroducing one or more of the components shown in FIG. 1 into apatient. In some embodiments, a sheath need not be used and instead onlya minimally invasive incision is used. In other embodiments, multipleminimally invasive incisions and/or sheaths 124 may be used forintroducing various devices into a patient. For example, one sheath 124may be used for introducing ablation device 100 and another sheath 124may be used for introducing positioner 114. Although devices and methodsof the present invention are often suitable for minimally invasiveprocedures, they may also typically be used in open surgical procedures,either with or without cardiopulmonary bypass, in various embodiments.

[0061] Referring now to FIG. 2, an embodiment of ablation device 100 isshown in further detail. Device 100 is shown from a bottom/angled viewto show a tissue contacting surfaces 224 of tissue contacting members102, ablation member 210, suction apertures 212 and sensors 214. Liketissue contacting members 102, tissue contacting surfaces 224 may begiven any configuration and sizes to contact cardiac tissue in an areaaround the tissue to be ablated. For example, in an embodiment as inFIG. 2 a tissue contacting surface 224 on one tissue contacting member102 may have a length of approximately 1.25 in. and a width ofapproximately 0.5 in., with a space between the two tissue contactingsurfaces measuring approximately 0.4 in. Such exemplary dimensions arein no way limiting, and all combinations of dimensions for one or moretissue contacting members 102 are contemplated. In some embodiments, asin FIG. 2, surfaces 224 may be flat and smooth. In other embodiments,surfaces 224 are textured, curvilinear or otherwise shaped to enhancecontact of tissue contacting members 102 with heart 140. Someembodiments may further include one or more surface features 222. Suchfeatures 222 may enhance friction between tissue contacting surfaces 224and epicardial tissue and/or may provide an area for placement ofadditional features, such as irrigation apertures for cooling tissue orthe like.

[0062] Ablation member 210 may include one or more ablation members fortransmitting one or more of a variety of ablation agents to epicardiumor other cardiac tissue. In some embodiments, as commonly shown in thedrawing figures, ablation member 210 may comprise a single, continuous,RF ablation coil or wire for transmitting RF energy to cardiac tissue.In other embodiments, ablation member 210 may be multiple radiofrequency devices or one or more cryogenic devices, ultrasound devices,laser devices, thermo-electric chip devices, chemical agent deliverydevices, biological agent delivery devices, light-activated agentdevices, thermal devices, microwave devices, or ablating drug deliverydevices. Other suitable ablation devices are also contemplated withinthe scope of the invention. Additionally, radio frequency ablationmembers 210 may be bipolar or unipolar in various embodiments. Inconjunction with any of these various embodiments, energy source 122 mayprovide any of the above-listed types of ablative energy or substance,any combination thereof or any other suitable ablative energy orsubstance.

[0063] Ablation member 210 may be given any configuration or size forablating cardiac tissue. In the embodiment shown in FIG. 2, for example,ablation member 210 has two linear portions disposed along most of thelengths of contacting surfaces 224 of tissue contacting members 102, andthe linear portions are continuous with a curved portion 226 so thatablation member 210 is generally U-shaped. Alternatively oradditionally, ablation member 210 may continue proximally from tissuecontacting members 102 in one or more arms 230 which eventually connectto wire 110 or other connective device. In some embodiments, curvedportion 226 may be eliminated so that ablation member 210 comprises twolinear ablation members connected to wire 110 via arms 230. In yet otherembodiments, arms 230 may be eliminated and ablation member 210 may becoupled directly to wire 110 without interposing arms.

[0064] Generally, ablation members 210 and tissue contacting member 102may have any shapes, sizes, configurations or combinations of shapes andsizes to produce a desired ablation pattern on epicardial or othertissue of a heart. In some examples, ablation members 210 and tissuecontacting members 102 are configured to partially or completelyencircle or surround one pulmonary vein. In other embodiments, they maybe configured to partially or completely surround two pulmonary veins onthe same side of the heart, such as the left superior and left inferiorpulmonary veins. In still other embodiments, the right and left inferiorpulmonary veins or the right and left superior pulmonary veins may bepartially or wholly encircled. And in still other embodiments, all fourpulmonary veins may be partially or completely encircled by ablationmembers 210 and tissue contacting member 102. Some of these embodimentsare described in further detail below, but it should be understood thatany possible configuration is contemplated within the scope of thepresent invention.

[0065] In some embodiments, all or a portion of ablation member 210 ortissue contacting member 102 may be steerable. Steerability means thatan ablation member 210 or tissue contacting member 102 may be adjustedto fit around or next to one or more pulmonary veins or to otherwiseassume a desired configuration. For example, some embodiments mayinclude a pull wire coupled with ablation member 210 and/or tissuecontacting member 102. The pull wire, when pulled, deflects ablationmember 210 and/or tissue contacting member 102 to one side or around acurved structure. Other embodiments may include pushable wires,combinations of flexible and stiff portion and/or the like to providesteerability.

[0066] In some embodiments, for example, it is desirable to ablateepicardial tissue in a circumferential pattern around one or morepulmonary arteries. Various configurations of tissue contacting members102 and ablation members 210 are contemplated for achieving suchablation patterns. For example, a retractable RF coil 240 or otherretractable ablation device may be incorporated into or used inconjunction with ablation member 210 as shown in FIG. 2. Retractablecoil 240 could be housed within tissue contacting member 102, forexample, and could be released when desired to surround or encircled oneor two pulmonary veins. As already described, the RF ablation member 210and/or the RF retractable coil 240 pictured in FIG. 2 may be replaced,in other embodiments, with devices using radio frequency energy,ultrasound energy, microwave energy, cryogenic energy, thermoelectricenergy or laser energy for ablating tissue. For example, ablation member210 in some embodiments comprises multiple thermoelectric chips disposedin a pattern on tissue contacting members 102.

[0067] Although ablation device 100 and ablation member 210 are oftenshown as being generally U-shaped, many other configurations arepossible. As described further below, a ablation device 100 may beconical in shape, with ablation member 210 being disposed in a circle atthe base of the cone which contacts cardiac tissue. In otherembodiments, device 100 may be configured as a flat patch and one ormore linear or curvilinear ablation members 210 may be incorporated intothe patch. For example, ablation device 100 may include a combination ofmultiple ablation members 210 to ablate a pattern on heart 140 such as:a first linear ablation member for contacting heart tissue between aleft pulmonary vein and a right pulmonary vein; a second linear ablationmember for contacting heart tissue at a location approximating a lineextending to the atrioventricular groove; and a third linear ablationmember for contacting heart tissue on a left atrial appendage. In suchan embodiments, one or more of ablation members 210 may overlap oneanother. In some embodiments involving multiple ablation members 210,each member may be controllable on a separate radio frequency channel orother energy transmission channel.

[0068] Tissue contacting members 102 optionally include one or moreattachment means for enhancing contact of ablation device 100 withepicardial or other cardiac tissue. In some embodiments, one or moresuction apertures 212 are used. Each suction aperture 212 generallyincludes a depressed surface and a small suction hole. The suction holeis connected to a lumen (not shown) within tissue contacting member 102,and the lumen is then couplable with a suction cannula 122 or connector216 for connecting to cannula 122. Suction apertures 212 may be givenany suitable configuration, size or pattern. For example, suction holesmay be disposed on tissue contacting member 102 is a largely linearpattern, as in FIG. 2. In other embodiments, suction apertures may bearranged in two parallel lines such that ablation member 210 is disposedbetween the two parallel lines of suction apertures 212. In stillanother embodiment, ablation device 100 may include one tissuecontacting member 102 having a conical shape, with the base of the conecontacting epicardial tissue and the entire conical tissue contactingmember 102 acting as one suction aperture.

[0069] In some embodiments, suction force may be applied via suctionapertures 210 with sufficient strength to allow for stabilization and/orpositioning of heart 140. For example, a physician may place ablationdevice 100 on a beating heart 140, apply suction, and hold heart 140 isa relatively stable or reduced-motion position while performing anablation procedure. The physician may also (or alternatively) turn orotherwise move heart 140, using ablation device 100, such as when adifferent angle of heart 140 would be advantageous for viewing ortreating a portion of heart 140. In these or other embodiments, suctionforce applied through suction apertures 212 may be of sufficientstrength to dissect through one or more layers of adipose tissuecovering epicardial tissue. Such dissection by suction apertures 212 mayallow for improved contact of the epicardial tissue by device and, thus,improved ablation. In alternative embodiments, suction apertures 212 maybe replaced or supplemented by other means for securing ablation device100 to epicardial tissue. For example, an adhesive may be applied totissue contacting surfaces 224. Such adhesives or other securing meansmay also be sufficiently strong, in some embodiments, to allow forpositioning and/or stabilization of heart 140.

[0070] Tissue contacting members 102 may also include one or moresensors 214 for sensing when tissue has been ablated. Sensors 214 mayinclude one or more thermal sensors, electrical sensors, thermoelectricsensors, microchips, thermistors, thermocouples and ultrasonic sensors.As shown in FIG. 2, some embodiments include two or more paired sensors214, with one sensor of each pair on one side of ablation member 210 andthe other sensor on the opposite side. In some embodiments, one sensor214 transmits a signal through epicardial tissue to its paired sensor214. If epicardial tissue between the two paired sensors 214 has beenablated, then energy will transmit poorly through that ablated tissue.Thus, the receiving sensor 214 will receive reduced or no energytransmitted from the transmitting sensor 214. If tissue between twopaired sensors has not been ablated, the signal should travel throughthe tissue with only slight reduction in strength. By using such pairedsensors 214 and comparing signals received in different pairs, areas ofablation can be compared, to determine if all desired areas for ablationhave been sufficiently ablated. Other configurations one or more sensors214 may also be used.

[0071] Referring now to FIG. 2a, another view of ablation device 100 asin FIG. 2 is shown, with ablation member 210 removed for clarity. Insome embodiments, tissue contacting members 102 include a linear trough250 in which ablation member 210 is placed, either removably orpermanently. Positioning ablation member 210 in trough 250 may provideimproved contact between ablation member 210 and epicardial tissue whilealso providing ablation device 100 with durability. Surface features 222are again shown in FIG. 2a. These features may simply enhance contact oftissue contacting members 102 with epicardial tissue or may also containadditional features, such as sensors, irrigation apertures for allowingpassage of irrigation fluid for cooling ablated tissue, small suctionapertures and/or the like.

[0072] Optionally, various embodiments of ablation device 100 mayfurther include at least one cooling member for cooling a portion ofablated epicardial tissue, epicardial tissue surrounding an ablatedarea, other nearby tissues and/or a portion of device 100. Coolingmembers are not shown in the drawing figures, for purposes of clarity.Generally, a cooling member may comprise any suitable device for coolinga tissue. In some embodiments, cooling member includes at least oneinlet port, for allowing introduction of a cooling substance into themember, a hollow internal cooling member, and at least one outlet portfor allowing egress of the cooling substance. The cooling substanceitself may be carbon dioxide, any other suitable gas, saline or anyother suitable liquid. In some embodiments, the hollow cooling membercomprises a tubular member disposed within tissue contacting member 102in general proximity with ablation member 210. In other embodiments,cooling member may comprise a chamber for containing cooling substanceor a series of irrigation holes for allowing cooling substance to flowout of tissue contacting member 102 to contact ablated or otherepicardial tissue. Many other suitable cooling apparatus arecontemplated for use within the scope of the present invention.

[0073] With reference now to FIG. 3, another embodiment of ablationdevice 300 is shown from a bottom-side view. Ablation device 300includes a tissue contacting member 302, coupled with an ablation member310 and a support member 304. As with some above-described embodiments,tissue contacting member includes a tissue contacting surface 324,tissue attaching means including multiple suction apertures 312 andmultiple artery securing arms 308. Tissue contacting member 302 isremovably couplable with a suction cannula 318 via a V-shaped suctionconnector 316. Ablation member 310 is coupled with energy transmittingwire 314 for coupling with an energy source (not shown). Support member304 includes a support arm 306 (shown partially in dotted lines, sinceit extends on the opposite side of tissue contacting member 302) forcoupling device 300 with a positioning device.

[0074] In ablation device 300, tissue contacting member 302, ablationmember 310 and support member 304 are all generally shaped as a squarewith a central area 303 and a top area 305 left open. Such aconfiguration may be used, for example, to contact and ablate epicardialtissue almost completely encircling one or more pulmonary veins. Leavingtop area 305 open may allow device 300 to be positioned around suchveins or other vessels while still providing almost circumferentialablation. In other embodiments, either central area 303, top area 305 orboth may be closed to provide for different contact and/or ablationpatterns on epicardial tissue. In still other embodiments, one or morehinges may be positioned on ablation device 300 to allow top area 305 tobe closed after positioning device 300 around one or two pulmonaryveins. Again, any configuration, shape, size, dimensions or the like arecontemplated within the scope of the invention.

[0075] Referring now to FIG. 4, another embodiment of ablation device400 comprises a largely flexible device which includes a tissuecontacting member 402 and an ablation member 410. Tissue contactingmember 402 may be made of any suitable, flexible material, such as asilicone, polyurethane, polycarbonate, another suitable polymer orcombination of polymers or the like. Tissue contacting member 402generally includes a tissue contacting surface 424 having multiplesuction apertures 412. Tissue contacting surface 424 may be slightlyconcave (as shown), flat or may have any other suitable shape. Suctionapertures 412 are disposed in two parallel lines, one line on eitherside of ablation member 410 and communicate with suction lumens 414 and416. Suction lumens 414, 416 may be coupled with one or more suctioncannulas or similar devices for providing suction force through suctionapertures 412. Other embodiments may include one common suction lumenfor connection to a suction cannula.

[0076] As with various embodiments described above, any suitableablation means may be used as ablation member 410 in device 400. In theembodiment shown, ablation member 410 comprises a linear radio frequencycoil. Ablation member 410 may extend beyond the length of tissuecontacting member 402, either in a proximal or distal direction and maybe coupled with a source of energy via a wire (not shown) or otherconnection device. In various embodiments, one or more of the featuresdescribed above, such as support members, retractable ablation elements,sensors, cooling members, positioning arms and/or the like may beincorporated into or used with ablation device 400. Alternatively,ablation device 400 may simply include tissue contacting member 402 andlinear ablation member 410. Such an embodiment may be advantageous forintroduction through a narrow, minimally invasive introducer sheath, dueto the device's flexibility and relatively small size. In oneembodiment, for example, device 400 may measure approximately 3.25 in.in length and approximately 0.9 in. wide and may further be deformableto a narrower configuration for insertion through a sheath. Furthermore,device 400 may be sufficiently flexible to conform to curved surfaces ofheart 140, allowing for enhanced contact with and ablation of epicardialtissue. Finally, it may sometimes be advantageous to ablate epicardialtissue in a linear pattern or in multiple line. Ablation device 400 maybe movable, to allow ablation in a first line, a second line, a thirdline and/or the like.

[0077] Referring now to FIG. 4a, a bottom-side view of ablation device400 is shown with ablation member removed. It can be seen that tissuecontacting member 402 may include a trough 420 in which ablation member410 may be positioned. In some embodiments, ablation member 410 may be aremovable piece which may be removably attached to tissue contactingmember 402, at least partially disposed within trough 420, so that oneablation member 410 may be used with multiple tissue contacting members402, one after another, for example if tissue contacting members 402 aresingle-use, disposable devices.

[0078]FIG. 5 shows yet another embodiment of ablation device 500,including a tissue contacting member without an ablation member beingshown. Device 500 is similar to ablation device 400, but tissuecontacting member 502 has one row of suction apertures 512 rather thantwo and ablation member, placed in ablation trough 520, overlays suctionapertures 512. Suction holes 522 shown in suction apertures 512demonstrate that the apertures sometimes include both a depressed orconcave surface and one or more holes communicating with a suctionlumen. The embodiment of ablation device 500 in FIG. 5 may beadvantageous for forming one or more linear ablations on heart 140 whenthere is minimal space in which to manipulate device 500 and/or when anarrow, minimally invasive incision or sheath is desired for insertionof device 500. Device 500 may be manufactured from any suitable materialor combination of materials, such as those described above, may use anysuitable form of ablation member and may include various additionalfeatures as desired.

[0079] Referring now to FIG. 6, ablation device as described withreference to FIGS. 4 and 4a is shown in position for performingepicardial ablation on a human heart 140. Generally, ablation device 400may be placed in any desired position on heart 140 for ablatingepicardial tissue. Thus, in various embodiments device may be placedadjacent one or both of the right pulmonary veins 142, 144, adjacent oneor both of the left pulmonary veins 148, 150, or in any other suitablelocation. Furthermore, ablation device 400 may be used to ablate tissuein a linear pattern at one location and then may be moved to ablatedtissue in a linear pattern in another location. As discussed above withreference to various embodiments, ablation device 400 may be introducedinto a patient via a minimally invasive device, such as a sheath 630 ortrocar, and may be coupled with a source of suction 120 via a suctioncannula 112 and with a source of ablative energy 122 via a wire 110 orother connective device.

[0080] Ablative device 400, as well as other embodiments of ablativedevices described above, may be positioned on heart 140 via apositioning device 602 which is introduced via a second minimallyinvasive incision or second sheath 620. Second sheath 620 may be placedat any suitable location on the patient to allow access to ablationdevice with the positioning device 602. Positioning device 602 may thenbe introduced through sheath and advanced to the position of ablationdevice 400. Positioning device 602 may then be used to secure device400, such as by opposable jaws 610 or any other suitable means, andposition device 400 in a desired location on heart 140. In someembodiments, positioning device may further be used to reposition device400 to perform ablation in multiple locations on heart 140. The proximalend of positioning device 602 may include a handle 604 for holding andmanipulating device 602 and one or more actuators 606, such as a triggerfor opening and closing opposable jaws 610 or other distally positionedend effectors of device 602. Examples of positioning device 602 mayinclude, but are not limited to, conventional minimally invasivesurgical devices such as laproscopic surgical devices and the like.

[0081] Referring now to FIG. 7, another embodiment of ablation device700 suitably includes at least one elongate shaft 702 having a proximalend 724 and a distal end 726, a jaw member 704 coupled with shaft 702near distal end 726, at least one ablation member 712, 714 coupled withjaw member 704, and a handle 706 and at least one actuator 708, 710 nearthe proximal end 724 for manipulating device 700, opening and closingthe jaw member, activating ablation member 712, 714 and the like. Device700 is generally configured to be introduced through a minimallyinvasive sheath, trocar or incision, though it may also be used in opensurgical procedures. Shaft 702 may be made of any suitable material,such as metal, ceramic, polymers or any combination thereof, and may berigid along its entire length or rigid in parts and flexible in one ormore parts. In various embodiments, the shaft may be malleable, mayarticulate about at least one joint and/or may be steerable forpositioning the device. In some embodiments, the ablation member iscoupled with a portion of the shaft.

[0082] Jaw member 704 may be disposed on or near distal end 726 of shaft702 and is generally configured to open and close to grasp epicardial orother tissue between the opposing jaws. For example, jaw member 704 maybe coupled with shaft 702 at a hinge point 730 to allow for such openingand closing motion. An ablation member is coupled with at least part ofjaw member 704. As with the above-described embodiments, the ablationmember may use any suitable energy source for ablating tissue. In someembodiments, multiple ablation members 712, 714 may be used. Forexample, one electrode 712 of a bipolar ablation member may be coupledwith one opposing jaw and another electrode 714 may be coupled with theother opposing jaw. Alternatively, ablation members 712, 714 may includeone unipolar ablation device or any of the ablation devices describedwith reference to various embodiments above. The jaw member and/or theablation member may be shaped to contact and ablate the epicardialtissue in a pattern such as, but not limited to, a U-shaped pattern, anL-shaped pattern, a circular pattern or a linear pattern. Actuators 708,710 may have one or more various functions, such as opening and closingjaw member 704, activating ablation members 712, 714, changing an angleof orientation of jaw member 704, straightening or bending jaw member704 and/or the like. One actuator 710, for example, may comprise atrigger-like actuator while another actuator 708 may comprise a turnabledial.

[0083] Generally, jaw member 704 may have any suitable configuration forcontacting a surface of a heart, for grasping epicardial or other tissueto be ablated and/or for placing ablation members 712, 714 in contactwith tissue to be ablated. As such, jaw members 714 may be straight,curved, bent or otherwise configured for contacting, grasping and/orablating tissue. In some embodiments, jaw member 704 may be adjustablevia an actuator 708, 710, so as to allow their shapes to be bent,straightened or the like during a procedure. With reference to FIG. 7a,one embodiment of a straight jaw member 718 may allow jaw member 718 tobe retracted within shaft (arrows). Retraction may help protect apatient as well as jaw member during insertion and advancement of thedevice within the patient. Again, ablation members 720, 722 on suchstraight jaw members 718 may be bipolar RF members, unipolar RF membersor any other suitable ablation devices.

[0084] Optionally, the device may further include an insulation memberat least partially surrounding the device to protect body structures inthe vicinity of the epicardial tissue to be ablated from damage due toheat or electrical current. Also optionally, the ablation member may beadjustable to deliver two or more varying amounts of ablative energy totwo or more locations on the epicardial tissue. Various embodiments mayfurther include at least one sensor for sensing a quantity of ablationprovided by the ablation member to the tissue.

[0085]FIG. 8 shows ablation device 700, as just described, in a positionfor performing an ablation procedure on epicardial tissue of heart 140.Device as shown will ablate in a pattern approximating two linesadjacent the right pulmonary veins 142, 144. It should be understood,from the foregoing descriptions of various embodiments, that jaw member704 and ablation members 712, 714 could alternatively be configured inany other suitable shape, size or configuration to ablate in otherpatterns on heart 140. Additionally, device 700 may be moved to avariety of positions to ablate multiple patterns in multiple locationson the epicardial tissue.

[0086] With reference now to FIG. 9, a method for ablating cardiactissue, such as epicardial tissue, suitably includes contacting cardiactissue with an ablation device 910, securing the device to the tissue920 and ablating at least a portion of the contacted, secured tissue930. Various embodiments of the invention will utilize additional stepsor sub-steps of these three basic steps, but it should be emphasizedthat any additional steps or variations are optional. For example, insome embodiments, contacting the cardiac tissue 910 is preceded byadvancing the device into the patient through a minimally invasiveintroducer device. Contacting the device with the tissue 910 may includepositioning the device using a positioning arm or other positioningdevice. In some embodiments, securing the device to the tissue 920 mayalso comprise invaginating a portion of epicardial tissue partiallywithin one or more suction apertures and/or may include using one ormore suction apertures to dissect through fatty tissue disposed overepicardium. Securing the device 920 may also involve securing withenough force to allow stabilization and/or positioning of the heartitself. And ablation of epicardial tissue 930 may involve ablation inany location or pattern as described above with reference to theinventive devices. Therefore, the descriptions of various methodsprovided herein are offered for exemplary purposes only and should notbe interpreted to limit the scope of the invention as described in theclaims.

[0087] Other aspects of a method for ablating epicardial tissue mayinclude imaging the epicardial tissue and an area surrounding the tissueto be ablated, using a visualization device. Such a device may becoupled with the ablation device or may be a separate imaging device. Insome embodiments, an insufflation device may be inserted between theepicardium and the pericardium and insufflation fluid or gas may beintroduced to form a space between the epicardium and pericardium. Thespace may be used to enhance visualization, allow for freer manipulationof devices near the site for ablation and the like. Another aspect mayinclude sensing ablation of epicardial tissue with one or more sensors,as described above. In some embodiments, tissue may optionally be cooledvia a cooling member and/or irrigation of fluid into contact with thetissue. Finally, the actual ablation of epicardial tissue may beaccomplished with any suitable ablation member and form of energy,including RF, thermoelectric, cryogenic, microwave, laser, ultrasound orthe like. In one embodiment, ablation is achieved and/or enhanced bydelivery of one or more drugs to the tissue.

[0088] In one embodiment, a method first includes advancing an ablationdevice through a minimally invasive introducer device into a patient andto a location for ablating epicardial tissue. The device is thencontacted with the epicardial tissue and positioned on the tissue with apositioning arm or other device inserted through the same or a separateminimally invasive introducer or incision. Positioning device, in someembodiments, may be a flexible, rigidifying positioner which allows forpositioning and then stabilizing with the same device. The ablationdevice may be placed in any suitable location for ablating epicardialtissue. In one embodiment, for example, ablation device will contacttissue at least partially encircling two pulmonary veins, such as theright superior and right inferior pulmonary veins. The ablation devicemay contact epicardial tissue directly adjacent the bases of the veinsbut may be configured to maintain a safe distance between the ablationmember on the device and the actual veins.

[0089] Once the epicardial tissue is contacted, the device may besecured to the tissue by securing means, such as suction or adhesive. Infact, the device may be secured to the tissue sufficiently in someembodiments to allow the heart to be stabilized and/or positioned usingthe device and a positioner. For example, a beating heart may bestabilized to reduce or eliminate motion during an ablation procedure ormay be pulled, turned or otherwise moved into an advantageous positionfor ablating, visualizing or treating the heart. Suction force may alsobe supplied in sufficient strength to dissect through a layer of adiposetissue overlying the epicardial tissue, which may provide improvedcontact of an ablation member with the epicardial tissue. Once thetissue is secured, at least a portion of the tissue may be ablated bydelivering energy to an ablation member (or members) on the device. Asalready described in detail, such energy may include any suitable energyand may additionally or alternatively include one or more ablativedrugs. After ablation, tissue may be cooled via cooling means and/orablation of tissue may be sensed with one or more sensors. When anablative procedure is complete, the device may be removed and placed inanother location on the heart for an additional procedure or may beremoved from the patient altogether.

[0090] While the present invention has bee shown and described withreference to various embodiment thereof, the above and other changes inform and detail may be made without departing from the spirit and scopeof the invention as defined in the following claims.

What is claimed is:
 1. A system for treating heart tissue to treat acardiac arrhythmia, the system comprising: at least one energytransmission member for applying energy to the heart tissue in a patternto treat the cardiac arrhythmia; at least one tissue securing membercoupled with the at least one energy transmission member for enhancingcontact of the energy transmission member with the heart tissue; and atleast one guiding member coupled with at least one of the energytransmission member and the tissue securing member for guiding theenergy transmission member and the tissue securing member to a locationfor treating the heart tissue.
 2. A system as in claim 1, furthercomprising at least one visualization member for enhancing visualizationof the heart tissue and the treatment location.
 3. A system as in claim2, wherein the at least one visualization member comprises at least oneof an optic imaging device, a thermal imaging device, an ultrasounddevice, an electrical imaging device and a Doppler imaging device.
 4. Asystem as in claim 3, wherein the optic imaging device comprises a fiberoptic device positionable to view a posterior portion of the hearttissue.
 5. A system as in claim 3, wherein the thermal imaging devicemeasures at least one heat transfer coefficient of the heart tissue todetermine at least one of a type and a thickness of the heart tissue. 6.A system as in claim 3, wherein the electrical imaging device measuresat least one of electrical resistance and impedance of the heart tissueto determine at least one of a type and a thickness of the heart tissue.7. A system as in claim 2, wherein the at least one visualization memberis removably coupled with at least one of the at least one energytransmission member, the at least one tissue securing member and the atleast one guiding member.
 8. A system as in claim 2, wherein the atleast one visualization member comprises at least one optic member foracquiring optic signals of an area to be visualized, and wherein thevisualization member includes at least one inflatable member coupledwith the visualization member at or near the optic member.
 9. A systemas in claim 8, wherein the at least one inflatable member provides aspace in a body cavity to enhance operation of the optic member.
 10. Asystem as in claim 8, wherein the at least one inflatable memberprovides a space between at least two body tissues to enhance operationof the optic member.
 11. A system as in claim 8, wherein the at leastone inflatable member comprises an inflation port in fluid communicationwith an inflation lumen coupled with the visualization member forallowing introduction of a liquid or a gas to inflate the inflatablemember.
 12. A system as in claim 8, wherein the at least one inflatablemember reduces motion of the heart tissue when applied to the hearttissue.
 13. A system as in claim 1, further comprising at least onepositioning device for contacting the heart tissue and positioning theheart tissue for treatment.
 14. A system as in claim 13, wherein the atleast one positioning device comprises a suction positioning device. 15.A system as in claim 13, wherein the at least one positioning devicereduces motion of a beating heart to further position the heart tissuefor treatment.
 16. A system as in claim 1, wherein the applied energy isselected from the group consisting of radio frequency energy, ultrasoundenergy, microwave energy, cryogenic energy, thermoelectric energy andlaser energy.
 17. A system as in claim 1, wherein the at least oneenergy transmission member contacts an epicardial surface of the hearttissue to transmit the energy, and wherein the energy is transmittedfrom the epicardial surface through the heart tissue to an endocardialsurface.
 18. A system as in claim
 17. wherein the energy is furthertransmitted through at least one of fat and connective tissue coveringat least part of the epicardial surface.
 19. A system as in claim 16,further comprising at least one grounding device for dispersing theenergy from a patient undergoing an energy transmission heart procedure.20. A system as in claim 16, further comprising at least one needlecoupled with the energy transmission member for insertion into the hearttissue to enhance the application of energy to the heart tissue.
 21. Asystem as in claim 20, wherein the energy is transmitted from a tip ofeach of the at least one needle.
 22. A system as in claim 20, whereinthe at least one needle is retractable.
 23. A system as in claim 22,wherein the at least one retractable needle is exposed and retracted viaa pneumatic member coupled with the energy transmission member.
 24. Asystem as in claim 22, wherein the at least one retractable needle isexposed and retracted automatically when the energy transmission membercontacts the heart tissue.
 25. A system as in claim 22, wherein a depthof penetration of the at least one retractable needle into the hearttissue is adjustable.
 26. A system as in claim 16, further comprising atleast one closed circuit feedback loop for measuring and regulatingoperation of the energy transmission member.
 27. A system as in claim16, wherein at least one of the energy transmission member and thetissue securing member further comprises at least one fluid aperture forapplying fluid to the heart tissue to enhance the application of energyto the heart tissue.
 28. A system as in claim 1, wherein at least oneenergy transmission member is coupled with at least one guiding membersuch that a change in shape of the guiding member causes a correspondingchange in shape of the energy transmission member.
 29. A system as inclaim 28, wherein the guiding member comprises a deformable linearmember its shape being adjustable by a user, and wherein the energytransmission member comprises a deformable linear member coaxiallycoupled with the guiding member so as to move with the guiding member.30. A system as in claim 29, wherein the guiding member is adjustable toat least partially encircle at least one pulmonary vein.
 31. A system asin claim 1, wherein the at least one tissue securing member comprises atleast one connector for removably coupling with the at least one energytransmission member.
 32. A system as in claim 31, wherein the at leastone tissue securing member is conformable to a surface topography of theheart tissue.
 33. A system as in claim 31, wherein a first longitudinalaxis of the tissue securing member and a second longitudinal axis of theremovably coupled energy transmission member are colinear.
 34. A systemas in claim 31, wherein a first longitudinal axis of the tissue securingmember and a second longitudinal axis of the removably coupled energytransmission member are parallel to one another.
 35. A system as inclaim 31, wherein a first longitudinal axis of the tissue securingmember and a second longitudinal axis of the removably coupled energytransmission member are offset from one another.
 36. A system as inclaim 31, wherein the at least one energy transmission member comprisesa linear member, and wherein the at least one connector comprises aplurality of connectors disposed along a length of the tissue securingmember for removably coupling the linear member with the tissue securingmember.
 37. A system as in claim 31, wherein the at least one tissuesecuring member allows compressive force to be applied between the atleast one energy transmission member and the heart tissue.
 38. A systemas in claim 31, wherein the at least one tissue securing membercomprises at least one vacuum applying member.
 39. A system as in claim38, wherein the at least one vacuum applying member comprises: at leastone vacuum lumen; at least one vacuum port in fluid communication withthe lumen for coupling the lumen with a vacuum source; and at least oneaperture in fluid communication with the lumen for applying vacuum forceto the heart tissue.
 40. A system as in claim 39, wherein the at leastone vacuum lumen comprises multiple, separate lumens, and wherein eachseparate lumen is in fluid communication with a separate vacuum port.41. A system as in claim 40, further comprising means for selectivelyapplying vacuum to one or more of the separate lumens without applyingvacuum to one or more other separate lumens.
 42. A system as in claim31, wherein the at least one tissue securing member comprises at leastone expansible balloon member.
 43. A system as in claim 42, wherein theat least one expansible balloon member comprises at least one fluidintroduction port for allowing introduction of a liquid or a gas toexpand the balloon member.
 44. A system as in claim 43, wherein the atleast one expansible balloon member comprises multiple, separate balloonmembers, and wherein each separate balloon member is in fluidcommunication with a separate fluid introduction port.
 45. A system asin claim 44, further comprising means for selectively introducing fluidinto one or more of the separate balloons without introducing fluid intoone or more other separate balloons.
 46. A system as in claim 31,wherein the tissue securing member prevents a portion of the hearttissue from being treated by the at least one energy transmissionmember.
 47. A system as in claim 46, wherein the tissue securing membercomprises at least one insulation material for preventing the portion ofthe heart tissue from being treated.
 48. A system as in claim 47,wherein the at least one insulation material further prevents the atleast one energy transmission member from contacting or harming other,non-cardiac tissue of the patient and from contacting or harming a userof the energy transmission member.
 49. A system as in claim 1, whereinthe at least one guiding member comprises at least one of an elongateshaft, a steerable guidewire and an introducer sheath.
 50. A system asin claim 49, wherein the steerable guidewire comprises a pushableguidewire having at least one relatively stiff portion and onerelatively flexible portion for positioning the energy transmissionmember in a location for treatment.
 51. A system as in claim 49, whereinthe steerable guidewire comprises a pullable guidewire to which tensionis applied to steer the guidewire to position the energy transmissionmember in a location for treatment.
 52. A system for treating hearttissue to treat a cardiac arrhythmia, the system comprising: at leastone therapeutic agent transmission member for applying at least onetherapeutic agent to the heart tissue in a pattern to treat the cardiacarrhythmia; at least one tissue securing member coupled with the atleast one energy transmission member for enhancing contact of the energytransmission member with the heart tissue; and at least one guidingmember coupled with at least one of the energy transmission member andthe tissue securing member for guiding the energy transmission memberand the tissue securing member to a location for treating the hearttissue.
 53. A system as in claim 52, wherein the therapeutic agenttransmission member comprises: at least one lumen; and at least oneaperture in the lumen for allowing passage of the at least onetherapeutic agent out of the lumen to contact the heart tissue.
 54. Asystem as in claim 53, further comprising at least one needle coupledwith the therapeutic agent transmission member for insertion into theheart tissue to enhance application of the at least one therapeuticagent to the heart tissue.
 55. A system as in claim 52, wherein thetherapeutic agent transmission member comprises: at least one needle;and at least one aperture adjacent a tip of each needle for allowingpassage of the at least one therapeutic agent out of the needle tocontact the heart tissue.
 56. A system as in claim 55, wherein the atleast one needle is retractable.
 57. A system as in claim 56, whereinthe at least one retractable needle is exposed and retracted via apneumatic member coupled with the therapeutic agent transmission member.58. A system as in claim 56, wherein the at least one retractable needleis exposed and retracted automatically when the therapeutic agenttransmission member contacts the heart tissue.
 59. A system as in claim56, wherein a depth of penetration of the at least one retractableneedle into the heart tissue is adjustable.
 60. A method for treatingheart tissue of a patient to treat a cardiac arrhythmia, the methodcomprising: advancing at least one treatment member coupled with atleast one tissue securing member through an incision on the patient;visualizing a treatment area in the patient with at least onevisualization member; contacting the heart tissue of the patient withthe treatment member and the tissue securing member; applying a force,through the tissue securing member, to enhance contact of the treatmentmember with the heart tissue; and treating the heart tissue, using theat least one treatment member.
 61. A method as in claim 60, wherein atleast one of the treatment member and the tissue securing member areadvanced through a port applied to the patient, the port having adiameter no greater than 5 cm.
 62. A method as in claim 60, wherein theadvancing step includes guiding at least one of the treatment member andthe tissue securing member using at least one guiding member.
 63. Amethod as in claim 62, wherein guiding comprises using a pushableguidewire having at least one relatively stiff portion and onerelatively flexible portion for positioning the treatment member in alocation for treatment.
 64. A method as in claim 62, wherein guidingcomprises using a pullable guidewire to which tension is applied tosteer the guidewire to position the treatment member in a location fortreatment.
 65. A method as in claim 60, further comprising using atleast one positioning device to position the heart tissue for treatment.66. A method as in claim 65, wherein using the at least one positioningdevice comprises applying suction to the heart tissue.
 67. A method asin claim 65, wherein using the at least one positioning device reducesmotion of the heart tissue.
 68. A method as in claim 60, whereincontacting the heart tissue comprises applying a suction force with thetissue securing member to increase a contact surface area of the tissuesecuring member with the heart tissue.
 69. A method as in claim 68,wherein applying the suction force further comprises providingconsistent contact force between the heart tissue and the tissuesecuring member.
 70. A method as in claim 68, wherein applying thesuction force comprises securing the tissue securing member and thetreatment member to the heart tissue, the tissue securing member and thetreatment member having the same cross-sectional shape.
 71. A method asin claim 60, wherein treating the heart tissue comprises applying energyto the heart tissue in a pattern to reduce or eliminate the cardiacarrhythmia.
 72. A method as in claim 71, wherein applying the energycomprises applying at least one of radio frequency energy, ultrasoundenergy, microwave energy, cryogenic energy, thermoelectric energy andlaser energy.
 73. A method as in claim 71, wherein applying the energycomprises applying energy to an epicardial surface of the heart, andwherein the energy is transmitted from the epicardial surface throughthe heart tissue to an endocardial surface.
 74. A method as in claim 73.wherein the energy is further transmitted through at least one of fatand connective tissue covering at least part of the epicardial surface.75. A method as in claim 71, further comprising dispersing the energyfrom the patient through at least one grounding device coupled with thepatient.
 76. A method as in claim 71, further comprising inserting atleast one needle into the heart tissue to enhance the application ofenergy to the heart tissue.
 77. A method as in claim 76, wherein theenergy is transmitted from a tip of each of the at least one needle. 78.A method as in claim 76, further comprising extending the at least oneneedle from a retracted position before applying the energy andretracting the at least one needle to the retracted position when theenergy has been applied.
 79. A method as in claim 78, further comprisingselecting a depth of penetration of the at least one retractable needleinto the heart tissue.
 80. A method as in claim 71, further comprising:measuring the application of energy to the heart tissue using at leastone closed circuit feedback loop; and regulating the application ofenergy to the heart tissue based on the measurement.
 81. A method as inclaim 71, further comprising applying fluid to the heart tissue toenhance the application of energy to the heart tissue.
 82. A method asin claim 60, wherein treating the heart tissue comprises applying atleast one therapeutic agent to the heart tissue in a pattern to reduceor eliminate the cardiac arrhythmia.
 83. A method as in claim 82,wherein applying the at least one therapeutic agent comprises infusingthe agent through at least one aperture in the at least one treatmentmember.
 84. A method as in claim 83, applying the at least onetherapeutic agent comprises infusing the agent through at least oneaperture in at least one needle coupled with the treatment member.
 85. Amethod as in claim 82, wherein applying the at least one therapeuticagent comprises: inserting at least one needle into the heart tissue toa desired depth; injecting the at least one agent into the heart tissue;and removing the at least one needle from the heart tissue.
 86. A methodas in claim 85, further comprising: extending the at least one needlefrom a retracted position for insertion into the heart tissue; andretracting the at least one needle to the retracted position afterinjection.
 87. A method as in claim 60, further including adjusting ashape of a guiding member coupled with the at least one treatment memberto alter the shape of the treatment member.
 88. A method as in claim 87,wherein adjusting the shape of the guiding member allows the treatmentmember to conform to a surface of the heart tissue.
 89. A method as inclaim 87, wherein adjusting the shape of the guiding member allows thetreatment member to at least partially encircle at least one pulmonaryvein.
 90. A method as in claim 60, further comprising removably couplingthe tissue securing member with the at least one treatment member.
 91. Amethod as in claim 90, further comprising conforming the tissue securingmember to a surface topography of the heart tissue.
 92. A method as inclaim 60, wherein applying force comprises applying compressive forcebetween the at least one treatment member and the heart tissue.
 93. Amethod as in claim 92, wherein applying the compressive force comprisesapplying vacuum force via at least one vacuum member of the tissuesecuring member.
 94. A method as in claim 93, further comprisingapplying the vacuum force through at least a portion of the vacuummember while not applying the vacuum force through at least anotherportion of the vacuum member.
 95. A method as in claim 92, whereinapplying the compressive force comprises applying force via at least oneexpansible balloon member.
 96. A method as in claim 92, furthercomprising preventing, using the tissue securing member, a portion ofthe heart tissue from being treated by the at least one treatmentmember.
 97. A method as in claim 96, wherein the tissue securing membercomprises at least one insulation material for preventing the portion ofthe heart tissue from being treated.
 98. A method as in claim 60,visualizing comprises using at least one visualization member selectedfrom the group consisting of an optic imaging device, a thermal imagingdevice, an ultrasound device, an electrical imaging device and a Dopplerimaging device.
 99. A method as in claim 98, further comprisingexpanding an expansible balloon coupled with the visualization membernear an optic element to enhance visualization.
 100. A method as inclaim 99, wherein expanding the balloon provides a space in a bodycavity to enhance operation of the optic member.
 101. A method as inclaim 99, wherein expanding the balloon provides a space between atleast two body tissues to enhance operation of the optic member.
 102. Amethod as in claim 99, wherein expanding the balloon reduces motion ofthe heart tissue when applied to the heart tissue.
 103. A method fortreating heart tissue of a patient to treat a cardiac arrhythmia, themethod comprising: advancing at least one treatment member and at leastone tissue securing member through an incision on the patient; removablycoupling the at least one treatment member with the at least one tissuesecuring member; visualizing a treatment area in the patient with atleast one visualization member; contacting the heart tissue of thepatient with the treatment member and the tissue securing member;applying a force, through the tissue securing member, to enhance contactof the treatment member with the heart tissue; and treating the hearttissue, using the at least one treatment member.
 104. A method as inclaim 103, wherein the treatment member is advanced through the tissuesecuring member.
 105. A method as in claim 103, wherein the treatmentmember and the tissue securing member are advanced through a minimallyinvasive port applied to the patient.